Primers ITS1, ITS2 and ITS4 detect the intraspecies variability in the internal transcribed spacers and 5.8S rRNA gene region in clinical isolates of fungi.

Restriction fragment length polymorphism analysis of the 5.8S rRNA gene and the internal transcribed spacers (ITS1 and ITS2) was used for examination of 66 isolates belonging to 19 species. Intraspecies variability was found in the examined region of 11 species (Candida albicans, C. catenulata, C. colliculosa, C. glabrata, C. kefyr, C. melinii, C. parapsilosis, C. guillermondii, C. solanii, C. tropicalis, Saccharomyces cerevisiae). Region of ITS-5.8S rDNA was amplified using the primers ITS1 and ITS4. The amplicons were digested by HaeIII, HinfI and CfoI. The recognized intraspecies variability was confirmed in the second step, in which the shorter fragments of this region were amplified using primers ITS1 and ITS2 and analyzed by capillary electrophoresis. Considerable intraspecific variability renders this method unsuitable for species identification, whereas it can be useful for epidemiological tracing of isolates.